Field
The present invention relates to a medical or dental device for dispensing a powdered medium that is fluidized by a compressed gas onto human or animal tissue or a tissue replacement material.
Description of Prior Art
Such a device is known from patent application WO 2007/014246 A2. The device for dispensing a powdered medium can be connected to a dental unit for supplying it with compressed gas and water and it includes a container for storing the powdered medium and a dispensing unit in the form of a handpiece with a nozzle through which the powdered medium together with the compressed gas can be dispensed to a treatment site. Compressed gas is supplied to the container and to the powder contained in it in order to convey the powdered medium out of the container and to the dispensing unit.
In practice, it is difficult to operate such a device with constant operating parameters. Thus it is often observed that the amount of powdered medium conveyed by the compressed gas out of the container to the dispensing unit varies greatly, for example, as a function of the filling level of the powdered medium in the container or as a function of the type of powdered medium, for example, its grain size. Since the powdered medium stored in the container is very fine, i.e., has small grain sizes and is often hygroscropic, it additionally frequently occurs that the powdered medium forms lumps in the container which also results in considerable variations in the amount of powdered medium conveyed through the compressed gas.